System and method for torque transducer and temperature sensor

ABSTRACT

A system includes a magnetostrictive sensor having a sensor head including a driving pole. The driving pole includes a driving coil that may receive a driving current and may emit a magnetic flux portion through a rotary structure. The sensor head also includes a sensing pole including a sensing coil that may receive the magnetic flux portion and may transmit a signal based at least in part on the received magnetic flux portion. The received magnetic flux portion is based at least in part on a force on the rotary structure. The sensor head also includes a temperature sensor disposed on the sensor head. The temperature sensor may measure a temperature of the rotary structure.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/973,301 entitled “System and Method for Torque Transducer andTemperature Sensor,” filed Dec. 17, 2015, which claims priority from andthe benefit of Provisional Patent Application No. 62/121,323, entitled“System and Method for Torque Transducer and Temperature Sensor,” filedFeb. 26, 2015. Each of the foregoing applications is hereby incorporatedby reference in its entirety.

BACKGROUND

The subject matter disclosed herein relates generally to sensors, andmore particularly to temperature sensors for magnetostrictive sensors.

Sensors are used in a variety of industries to sense vibration, torque,speed, force, position, temperature, and other parameters. In certainapplications, the performance of the sensor may decrease due toelectrical and/or magnetic interference, temperature fluctuations, andstress, among others. Unfortunately, separate temperature sensors maycause electrical interference, magnetic interference, or be affected bytemperature gradients.

BRIEF DESCRIPTION

Certain embodiments commensurate in scope with the present disclosureare summarized below. These embodiments are not intended to limit thescope of the claims, but rather these embodiments are intended only toprovide a brief summary of certain embodiments. Indeed, embodiments ofthe present disclosure may encompass a variety of forms that may besimilar to or different from the embodiments set forth below.

In a first embodiment, a system includes a magnetostrictive sensorhaving a sensor head including a driving pole. The driving pole includesa driving coil that may receive a driving current and may emit amagnetic flux portion through a rotary structure. The sensor head alsoincludes a sensing pole including a sensing coil that may receive themagnetic flux portion and may transmit a signal based at least in parton the received magnetic flux portion. The received magnetic fluxportion is based at least in part on a force on the rotary structure.The sensor head also includes a temperature sensor disposed on thesensor head. The temperature sensor may measure a temperature of therotary structure.

In a second embodiment, a system includes a magnetostrictive sensor headincluding a driving coil coupled to a driving pole extending from asensor head core, that may receive a driving current, and that may emita magnetic flux portion through a rotary structure, and a sensing coilcoupled to a sensing pole extending from the sensor head core. Thesensing coil may receive the magnetic flux portion, the sensing coil maytransmit a first signal based at least in part on the received magneticflux portion, and the received magnetic flux portion is based at leastin part on a force on the rotary structure at a section of the rotarystructure opposite the magnetostrictive sensor head. The system alsoincludes a temperature sensor coupled to the magnetostrictive sensorhead. The temperature sensor transmits a second signal based on thetemperature of the section of the rotary structure.

In a third embodiment, a method includes generating a magnetic fluxportion with a driving coil coupled to a driving pole of amagnetostrictive torque sensor and directing the magnetic flux portionthrough the rotary structure and a sensing pole of the magnetostrictivetorque sensor. The rotary structure comprises a ferromagnetic material.The method also includes detecting the magnetic flux portion with asensing coil coupled to the sensing pole. The sensing coil may generatea torque signal based at least in part on a torque on the rotarystructure. The method also includes measuring a temperature of therotary structure with a temperature sensor disposed within themagnetostrictive torque sensor. The temperature sensor may generate atemperature signal. The method also includes determining the torque onthe rotary structure based at least in part on the torque signal fromthe sensing coil and the temperature signal from the temperature sensor.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the presentdisclosure will be better understood when the following detaileddescription is read with reference to the accompanying drawings in whichlike characters represent like parts throughout the drawings, wherein:

FIG. 1 is a side view of an embodiment of a magnetostrictive sensingsystem, wherein the magnetostrictive sensing system includes atemperature sensor in accordance with the present disclosure;

FIG. 2 is a side view of an embodiment of the magnetostrictive sensingsystem of FIG. 1, wherein the magnetostrictive sensing system includes acontroller integrated with a sensor head in accordance with the presentdisclosure

FIG. 3 is a top view of an embodiment of the magnetostrictive sensingsystem of FIG. 1, wherein the magnetostrictive sensing system includes atemperature pole in accordance with the present disclosure;

FIG. 4 is a perspective view of an embodiment of the magnetostrictivesensing system of FIG. 3, wherein the temperature pole includes thetemperature sensor and a shield in accordance with the presentdisclosure;

FIG. 5 is a perspective view of an embodiment of the magnetostrictivesensing system of FIG. 4, wherein the temperature pole includes thetemperature sensor in accordance with the present disclosure; and

FIG. 6 is a perspective view of an embodiment of the magnetostrictivesensing system of FIG. 3, wherein the temperature sensor is a coilwrapped around the temperature pole in accordance with the presentdisclosure.

DETAILED DESCRIPTION

One or more specific embodiments of the present disclosure will bedescribed below. In an effort to provide a concise description of theseembodiments, all features of an actual implementation may not bedescribed in the specification. It should be appreciated that in thedevelopment of any such actual implementation, as in any engineering ordesign project, numerous implementation-specific decisions must be madeto achieve the developers' specific goals, such as compliance withsystem-related and business-related constraints, which may vary from oneimplementation to another. Moreover, it should be appreciated that sucha development effort might be complex and time consuming, but wouldnevertheless be a routine undertaking of design, fabrication, andmanufacture for those of ordinary skill having the benefit of thisdisclosure.

When introducing elements of various embodiments of the presentdisclosure, the articles “a,” “an,” “the,” and “said” are intended tomean that there are one or more of the elements. The terms “comprising,”“including,” and “having” are intended to be inclusive and mean thatthere may be additional elements other than the listed elements.

In certain embodiments, such as oil and gas and energy applications,magnetostrictive sensors may be used to measure the torque of a shaft.Magnetostrictive torque sensors for such applications employ a sensingmethod in which a magnetic field is generated in the sensor by passingelectric current through an excitation coil. In magnetostrictive torquesensors, this magnetic field permeates the shaft and returns back to asensing coil (e.g., a pick-up coil) of the sensor. The output of thesensor coil is an electrical signal that depends at least in part on thetotal magnetic reluctance of this loop through the shaft. Part of thetotal magnetic reluctance is established by the air gap between thecoils and the shaft and part of the total magnetic reluctance isestablished by the shaft itself with the magnetic reluctance of theshaft changing as a function of torque on the shaft.

In general, non-contact magnetostrictive torque sensors are used withshafts that have been pre-magnetized (e.g., treated). Pre-magnetizationof the shaft may facilitate torque measurements by amplifying theintrinsic magnetostrictive properties of the shaft. As such, themagnetic flux generated due to the shaft torque may be detected by thenon-contact magnetostrictive torque sensor. However, not all equipmentor systems include pre-magnetized (e.g., treated) shafts. For example,in certain equipment, torque measurements may not have been desired atthe time of manufacturing the equipment or the torque may be measured byother techniques that did not utilize magnetostrictive sensors (e.g.,non-contact magnetostrictive sensors).

Retro-fitting systems having untreated shafts with non-contactmagnetostrictive sensors (e.g., if torque measurements are desired postmanufacturing) may be costly and inefficient. For example, the untreatedshaft may need to be removed from the equipment for treatment togenerate a magnetized shaft (e.g., a treated shaft). Accordingly, shafttreatment after equipment manufacturing or after system assembly mayincrease labor and equipment costs associated with treated shaftsystems. Furthermore, in equipment that uses treated shafts (e.g.,magnetized shafts), certain conditions may decrease the magnetization ofthe shaft (e.g., equipment overheating) over time, thereby decreasingamplification of the shaft's magnetostrictive properties, weakening themagnetic field flowing through the shaft, or resulting in inaccuratetorque measurements, or any combination thereof. Therefore, it may beadvantageous to develop a non-contact magnetostrictive sensor that maybe used with untreated (non-magnetized) rotary shafts. Non-contactmagnetostrictive sensors that may be used with untreated rotary shaftsmay increase the accuracy of the torque measurements and facilitateretro-fitting existing systems that do not have treated shafts with anon-contact magnetostrictive sensor. In this way, equipment may bemanufactured and/or retro-fit with non-contact magnetostrictive sensorsfor torque measurement without the costs associated with treatment(e.g., magnetization) of the shaft. In addition, production efficiencyfor the equipment may be increased due, in part, to reducing processingsteps generally associated with magnetization of the shaft.

The magnetostrictive torque sensor may include a driving coil togenerate magnetic flux (e.g., the magnetic field) that passes throughthe shaft (e.g., a ferromagnetic material) and is sensed by the sensingcoil. Changes in the measured magnetic flux depend partly on the changesin magnetic permeability of the shaft, which in turn are related to theamount of force applied to the shaft. Therefore, measurement of themagnetic flux passing through the shaft may be used to sense and/orcalculate the value of the applied force (e.g., torque). However, themagnetic properties of the shaft may change as a result of heat or otherfactors associated with a system that employs a magnetostrictive sensor.As such, the magnetic flux passing through the shaft (e.g., theferromagnetic material) may also change. For example, temperaturevariations of the shaft may affect (e.g., change) the shaft'selectromagnetic properties (e.g., electrical conductivity and magneticpermeability). The changes in the electromagnetic properties of theshaft may cause variations in the signal received by themagnetostrictive sensor. Consequently, the torque measurement derivedfrom the signals received and transmitted by the sensing coil may bedifferent than the actual torque on the shaft. In addition, variationsin the electromagnetic properties of the sensor coils, may also affecttorque measurements. Therefore, it may be desirable to measure atemperature of the shaft at or proximate to where the torque measurementis taken during operation of the shaft, and use the temperaturemeasurement to compensate for changes in the magnetic permeability ofthe shaft caused by the temperature variations. In this way, theaccuracy of the torque measurements may be increased. Accordingly, thepresent disclosure provides a non-contact magnetostrictive torque sensorwith an integrated temperature sensor that may measure a temperature ofthe shaft or other target surfaces.

In addition to measuring the surface temperature of the shaft, it may bedesirable to generate temperature measurements while the shaft isrotating. Real-time temperature measurements (e.g., during shaftrotation) may generate a more accurate temperature measurement comparedto temperature measurements taken after the shaft has stopped rotating.For example, a temperature of the shaft after the shaft has stoppedrotating may be less than a temperature of the shaft during rotation.Moreover, once the shaft has stopped rotating, torque is not beingapplied to the shaft. Therefore, adjusting torque measurements with atemperature of a non-rotating shaft may generate inaccurate results. Theplacement of the temperature sensors may also affect the torquemeasurements. For example, if a stand alone or other non-contactingtemperature sensor is positioned near a torque sensitive area (e.g.,near the sensing coil) of the torque sensor, torque measurements may beless accurate due to interference of the temperature sensor with themagnetic field. That is, the temperature sensor may affect the magneticflux through the torque sensor, resulting in less accurate torquemeasurements. Similarly, if the temperature sensor is positioned remotefrom the torque sensor, such that the temperature sensor does not affecttorque measurements, the temperature measurements may not correspond tothe temperature of the shaft at or near the torque sensor due, in part,to a temperature gradient of the shaft between the torque sensor and thetemperature sensor. That is, the shaft temperature at the torque sensorand the sensed temperature may be different because heat from the shaftdissipates away from the shaft, thereby causing a temperature gradientwith a higher temperature near the shaft and a lower temperature nearthe temperature sensor.

In addition, combining signals from two separate sensors (e.g., a torquesensor and a remote temperature sensor) may be difficult to process, anda signal to noise ratio may increase due to additional cabling used totransmit the signals from the two stand alone sensors to a singleprocessor. Integration of the temperature sensor with the torque sensormay reduce the signal to noise ratio and may enable the torque andtemperature measurements to be taken from the same section of the shaft.Moreover, the integrated temperature sensor may be positioned within atorque measurement neutral region of the torque sensor, such that thetemperature sensor does not interfere with the magnetic flux through thetorque sensor and the shaft. For example, the torque measurement neutralregion may be a magnetic neutral region or any other region on thetorque sensor that does not interfere with the magnetic flux between thedrive coil, shaft, and sensing coil. Additionally, or in thealternative, the torque measurement neutral region may be any region inwhich the magnetic flux from multiple drive coils may be readilycompensated, such as via addition or subtraction of a common magneticfield flux. Further, by integrating the temperature sensor with thetorque sensor, both sensors may use the same printed wiring board (PWB)or printed circuit board (PCB) for signal processing, therebyfacilitating signal integration.

FIG. 1 is a side view of an embodiment of a torque sensing system 10that includes a temperature sensor 12 in accordance with the presentdisclosure. The torque sensing system 10 may be used for sensing a forceapplied to a shaft 14 (e.g., a rotating shaft, a rotor, or any rotarystructure) of a machine or equipment 13, such as a turbomachine (e.g., aturbine engine, a compressor, a pump, or a combination thereof), agenerator, a combustion engine, or a combination thereof. The machine orequipment includes a driver 15 (e.g., reciprocating engine, combustionengine, turbine engine, electric motor) that applies a force to theshaft 14 and enables the shaft 14 to rotate and drive a load 16 (e.g.,electrical generator, compressor, pump, etc.) of the machine orequipment. The shaft 14 may include ferromagnetic materials including,but not limited to, iron, steel, nickel, cobalt, alloys of one or moreof these materials, or any combination thereof. In certain embodiments,the shaft is untreated (e.g., non-magnetized). In other embodiments, theshaft is treated (e.g., magnetized). The torque sensing system 10includes a sensor head 20 that forms a housing 21 for the torque sensingsystem 10. The sensor head 20 is positioned proximate to the shaft 14,thereby forming a gap 22 between the sensor head 20 and a shaft surface24. For example, the sensor head 20 may be disposed adjacent to a shaftsection 23 that is substantially opposite the torque sensing system 10.As such, the torque sensing system 10 may measure a torque of the shaft14 at the shaft section 23. In addition, because the temperature sensor12 is integrated with the torque sensing system 10, the temperaturesensor 12 may measure the temperature of the shaft section 23. As such,both the torque and temperature of the shaft 14 are measured at theshaft section 23. The sensor head 20 may be coupled to a frame orfixture to maintain the sensor head 20 in the proper orientation and/orposition, and to facilitate maintaining the gap 22 constant.

The sensor head 20 has a core 26 that may be formed from a ferromagneticmaterial similar to or different from the ferromagnetic material of theshaft 14. The core 26 has at least two ends, such as a driving pole 28and a sensing pole 30. As discussed in further detail below, in certainembodiments, the core 26 may have more than two ends. A driving coil 32and a sensing coil 36 are disposed about (e.g., wrapped around) thedriving pole 28 and the sensing pole 30, respectively. A power source 38(e.g., electrical outlet, electrical generator, battery, etc.) providespower to controller 42, and an excitation source (ES) 40 provides an ACcurrent 39 (e.g., driving current) to the driving coil 32. The drivingcurrent passes through the driving coil 32 to induce a magnetic fluxportion 50 that emanates from the driving coil 32. In the illustratedembodiments, a controller 42 is electronically coupled to the excitationsource 40 and is configured to control characteristics of the firstdriving current delivered to the driving coil 32 by the excitationsource 40. For example, the controller 42 may control the frequency,amplitude, or the like, of the first driving current. The controller 42may be coupled to the excitation source 40 by wired or wirelessconnections. Wireless communication devices, such as radio frequency(RF) transmitters, may be integrated with the controller 42 to transmitthe signals to an RF receiver integrated with the excitation source 40.In certain embodiments, the controller 42 is integrated into the torquesensing system 10. For example, FIG. 2 illustrates the controller 42disposed within the core 26 of the sensor head 20.

The controller 42 may include a distributed control system (DCS) or anycomputer-based workstation that is fully or partially automated. Forexample, the controller 42 may be any device employing a general purposeor an application-specific processor 46, both of which may generallyinclude memory circuitry 48 for storing instructions related tofrequencies, amplitudes of currents, for example. In addition, thememory circuitry 48 may include instructions and algorithms forintegrating sensor signals (e.g., torque and temperature signals) andcompensating torque measurements based on the temperature signal (e.g.,temperature of the shaft 14). The processor 46 may include one or moreprocessing devices, and the memory circuitry 48 may include one or moretangible, non-transitory, machine-readable media collectively storinginstructions executable by the processor 46 to perform the methods andcontrol actions described herein.

Such machine-readable media can be any available media other thansignals that can be accessed by the processor or by any general purposeor special purpose computer or other machine with a processor. By way ofexample, such machine-readable media can include RAM, ROM, EPROM,EEPROM, CD-ROM, or other optical disk storage, magnetic disk storage orother magnetic storage devices, or any other medium which can be used tocarry or store desired program code in the form of machine-executableinstructions or data structures and which can be accessed by theprocessor or by any general purpose or special purpose computer or othermachine with a processor. When information is transferred or providedover a network or another communications connection (either hardwired,wireless, or a combination of hardwired or wireless) to a machine, themachine properly views the connection as a machine-readable medium.Thus, any such connection is properly termed a machine-readable medium.Combinations of the above are also included within the scope ofmachine-readable media. Machine-executable instructions includes, forexample, instructions and data which cause the processor or any generalpurpose computer, special purpose computer, or special purposeprocessing machine to perform a certain function or group of functions,such as combining (e.g., integrating) the torque and temperature signalsto determine the actual torque measurements.

As illustrated in FIG. 1, a magnetic flux portion 50 permeates the shaft14, passes through the sensing coil 36, and returns to the driving coil32 via the core 26, thereby forming a loop through the torque sensor 10and the shaft 14. The sensing coil 36 may be used to measure themagnetic flux portion 50 exiting the shaft 14. A force (e.g.,compressive, tensile, torsional, etc.) applied to the shaft 14 maychange the magnetic permeability of the shaft 14, thereby causing themagnetic flux portion 50 to change. As such, the torque applied to theshaft 14 may be determined based on the change in magnetic flux portion50 received by the sensing coil 36 relative to the magnetic flux portion50 emitted by the driving coil 32. For example, the sensing coil 36 isconfigured to transmit a torque signal indicative of the changes (e.g.,difference) in the magnetic flux portion 50 to the controller 42. Theprocessor 46 of the controller 42 may process the torque signal receivedfrom the sensing coil 36 to calculate the force applied to the shaft 14.That is, the processor 46 may execute pre-stored and/or user-definedalgorithms in the memory 48 to calculate the magnitude of the forceapplied to the shaft 14 based on the characteristics of the shaft 14,the sensor head 20, and the driving current.

The torque signal from the sensing coil 36 may be communicated by wiredor wireless connections to the controller 42. In some embodiments,wireless communication devices, such as RF transmitters, may beintegrated with the sensor head 20 (e.g., proximate to the sensing coil36) to transmit the signals to an RF receiver 52 integrated with thecontroller 42. For example, the sensing coil 36 may transmit a torquesignal 54 to the receiver 52. The receiver 52 may include electroniccomponents (e.g., an amplifier, filter, or the like) that condition thetorque signal 54 before transmitting the torque signal 54 to theprocessor 46. In other embodiments, the torque signal 54 is conditionedafter being processed by the processer 46 of the controller 42.

As discussed above, a temperature of the shaft 14 may vary duringoperation of the equipment 16. This temperature variation may affect thepermeability of the magnetic flux portion 50, thereby affecting thetorque measurements. Consequently, without the disclosed embodiments,the determined torque measurement for the shaft 14 may not be the actualtorque. Therefore, the temperature of the shaft 14 may be measured andused as a compensation factor for compensating the torque measurementsbased at least in part on the temperature variations. However, asdiscussed above, the position of the temperature sensor 12 relative tothe shaft 14 may affect the magnetic flux portion 50 (e.g., if thetemperature sensor is too close to the shaft 14) and/or the temperaturemeasurements (e.g., if the temperature sensor is too far from the shaft14). Therefore, integrating the temperature sensor 12 with the torquesensing system 10 may enable the temperature sensor 12 to generateaccurate temperature measurements of the shaft 14 without interferingwith the magnetic flux portion 50. In addition, the temperature sensor12 may provide real-time temperature measurements during rotation of theshaft 14. As such, the torque sensing system 10 may generate bothaccurate torque and temperature measurements during rotation of theshaft 14. For example, the sensed temperature may be used to compensatefor effects temperature changes of the shaft 14 during rotation may haveon the magnetic permeability of the shaft 14. In this way, thetemperature sensor 12 may improve the accuracy of torque measurements,and thus enable better control of the machine or equipment 16, such as aturbomachine (e.g., a turbine engine, a compressor, a pump, or acombination thereof), a generator, a combustion engine, or a combinationthereof.

To reduce or eliminate magnetic flux disturbance between the torquesensing system 10 and the shaft 14, the temperature sensor 12 isdisposed in a torque measurement neutral region 56, e.g., on the housing21. The torque measurement neutral region 56 may be at any region of thetorque sensing system 10 that does not interfere with the loop of themagnetic flux portion 50 flowing through the torque sensing system 10and the shaft 14. For example, in the illustrated embodiment the torquemeasurement neutral region 56 is on the housing 21 away from the poles28, 30. In some embodiments, the torque measurement neutral region 56may be an axis centered between the driving pole 28 and the sensing pole30. However, the torque measurement neutral region 56 may be between twosensing poles 30, in the core 26, or any other magnetic neutral regionwithin the torque sensing system 10. In certain embodiments, the torquemeasurement neutral region 56 may be within a magnetic neutral region.For example, the torque measurement neutral region 56 may have adecreased magnetic permeability compared to the poles 28, 30. In otherembodiments, the torque measurement neutral region 56 may not have anymagnetic permeability. Therefore, by positioning the temperature sensor12 within the torque measurement neutral region 56, the temperaturesensor 12 may not interfere with the magnetic flux portion 50 flowingthrough the core 26 (e.g., via the poles 28, 30), which has a highmagnetic permeability compared to the torque measurement neutral region56.

It may be desirable for the temperature sensor 12 to be a non-contactsensor. As such, the temperature sensor 12 may measure the shafttemperature without having to be in direct contact with the shaftsurface 24. In this way, magnetic flux disturbance associated withcontact sensors (e.g., thermocouples, thermistors, resistancetemperature detectors, or any other temperature sensor in direct contactwith the shaft surface 24) may be mitigated. The system 10 may includeone or more temperature sensors 12 in the torque measurement neutralregion 56. In certain embodiments, the temperature sensor 12 may be aninfrared (IR) sensor or other radiative heat/temperature sensor. The IRsensor may be disposed on an integrated circuit (IC) 57 that is coupledto the sensor head 20. For example, IR sensor may be disposed on thecore 26, an additional pole, or any other portion of the sensor head 20that is within a magnetic neutral region, as discussed below withreference to FIGS. 4 and 5. In other embodiments, the temperature sensor12 may be a pyroelectric sensor or a thermopile sensor. The pyroelectricsensor measures a temperature voltage generated by the shaft 14 duringheating and/or cooling. The controller 42 determines the temperature ofthe shaft 14 based on the temperature voltage sensed by the pyroelectricsensor. If the temperature sensor 12 is a thermopile, the thermopilesenses thermal energy (e.g., radiation 58) from the shaft 14, andconverts the thermal energy to an electrical signal used to determinethe temperature of the shaft 14. In this way, the temperature sensor 12may be adjacent to a torque measurement location (e.g., the shaftsection 23), and a suitable distance away from the shaft surface 24. Assuch, the temperature sensor 12 may accurately measure the temperatureof the rotating shaft 14 without disturbing the magnetic flux portion50.

The infrared sensor may sense thermal radiation (e.g., IR radiation 58)emitted by the shaft 14 during rotation, and convert emitted IRradiation into an electrical temperature signal 59 (e.g., a voltage).The temperature sensor 12 transmits the temperature signal 59 to thecontroller 42 for processing. For example, the temperature signal 59 maybe combined with the torque signal 54 in the receiver 52, therebygenerating a combined signal 61. Similar to the torque signal 54 fromthe sensing coil 36, the temperature signal 59 may also be conditionedwith electronic components, such as an amplifier, a filter, or the like,before or after combining with the torque signal 54 or processed by theprocesser 46 of the controller 42. Additionally, in certain embodiments,the signals 54, 59 may be combined in the processor 46, rather than inthe receiver 52. The memory 48 may include instructions and algorithmsexecutable by the processor 46 to combine the signals 54, 59 andcompensate the measured torque based on the measured temperature (e.g.,the signal 59). The temperature signal 59 may be communicated by wiredor wireless connections to the controller 42, as discussed above withrespect to the torque signal 54.

FIG. 3 is a top view of a sensor head 60 having the temperature sensor12 disposed on a pole of the torque sensing system 10. Similar to thesensor head 20, the sensor head 60 includes a core 64 fabricated fromany ferromagnetic material, e.g., iron, steel, nickel, cobalt, or othersuitable magnetic material. The core 64 includes a cross axis yoke 68with a cross yoke portion 70. Four members 74, 76, 78, and 79 of thecross axis yoke 68 extend radially outward in a plane from the yokeportion 70. The four members 74, 76, 78, and 79 are substantiallyorthogonal to each other around the yoke portion 70. Each of the fourmembers 74, 76, 78, and 79 may extend from the yoke portion 70 in anyconfiguration and for any length that enables each member to operate asdescribed herein. In some embodiments, the yoke 68 may have any numberof members, such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more extendingradially from the yoke portion 70. For example, in the illustratedembodiments, the yoke 68 includes an additional member 80. The members74, 76, 78, 79, and 80 may be angularly spaced apart by approximately10, 20, 30, 40, 45, 60, 75, 90, 120, or 135 degrees, or any combinationthereof. In the illustrated embodiment, the members 74, 76, 78, and 79are angularly spaced apart by approximately 90 degrees, and the member80 is angularly spaced apart from the members 74, 79 by an acute angle81.

FIG. 4 is a perspective view of the sensor head 60 illustrated in FIG.3. As illustrated in FIG. 4, the driving pole 28 extends outward fromthe yoke portion 70, perpendicular to a planar surface defined by theyoke 68. In addition, the members 74, 76, 78, 79, and 80 extend outwardfrom the yoke 68 substantially perpendicular to the planar surfacedefined by the yoke 68 and substantially parallel to driving pole 28.The sensing poles 30 extend from distal ends 82 of each respectivemember 74, 76, 78, and 79. Similarly, a temperature pole 86 extends froma distal end 90 of the member 80. In certain embodiments, the poles 28,30, and 86 each extend an equal distance from the respective member 74,76, 78, 79, and 80, such that the poles 28, 30, and 86 have the samelength. To minimize variations in the gap 22 (e.g., between the shaft 14and each respective pole 28, 30, and 86), the sensor head 60 may berounded (e.g., dome-shaped). For example, the members 74, 76, 78, 79,and 80 may be oriented at an acute angle (e.g., less than 90 degrees)from the planar surface defined by the yoke 68, thereby forming arounded sensor head 60. In this way, the equal length poles 28, 30, 86may follow a contour of the shaft 14, and the gap 22 between the shaft14 and each respective pole 28, 30, 86 is the same. In embodiments wherethe members 74, 76, 78, 79, and 80 are substantially perpendicular tothe planar surface defined by the yoke 68, the poles 28, 30, and 86 mayeach have a variable length. The variable length for each pole 28, 30,86 may facilitate maintaining a substantially constant gap 22 betweenthe shaft 14 and each respective pole 28, 30, 86. Therefore, similar toembodiments having a rounded sensor head, a sensor head having variablelength poles 28, 30, and 86 may follow the contour of the shaft 14.

The temperature pole 86 is disposed within the torque measurementneutral region 56 (e.g., between the members 74, 76, 78, and 79), suchthat the temperature pole 86 does not interfere with the magnetic fluxportion 50. For example, the member 80 may be arranged substantiallyparallel with the axis of the shaft 14, such that the temperature pole86 is disposed along the axis of the shaft 14. In certain embodiments,the temperature pole 86 is centered between two sensing poles 30. Inthis way, the temperature sensor 12 may be integrated into the torquesensing system 10, and measure the temperature of the shaft 14 duringrotation of the shaft 14, rather than measuring the shaft temperaturewhen the shaft 14 is static (e.g., not rotating).

In certain embodiments, the temperature pole 86 is configured to besubstantially or completely insensitive to the magnetic flux portion 50.That is, the temperature pole 86 does not sense (e.g., measure) thetorque of the shaft 14 and/or is impermeable to the magnetic fluxportion 50. In some embodiments, the core 64 may have any number ofpoles (including driving poles, sensing poles, and temperature poles)extending from the yoke 68 that enables the core 64 to operate asdescribed herein. For example, the core may have one driving pole and 1,2, 3, 4, 5, 6, 7, 8, 9, 10 or more sensing poles and temperature polesextending from the yoke 68.

As discussed above, the driving pole 28 includes the driving coil 32 fordriving the magnetic flux portion 50 into the shaft 14. Similarly, thesensing poles 30 include sensing coils 36 wrapped around each respectivemember 74, 76, 78, and 79. The sensing coils 36 detect the magnetic fluxportion 50 after the magnetic flux portion 50 passes through the shaft14. The temperature sensor 12 is disposed on the temperature pole 86 andsenses the heat (e.g., IR heat 58) from the rotating shaft 14. Forexample, the temperature sensor 12 may be at a distal end 90 of thetemperature pole 86, in the yoke 68 of the member 80, or any othersuitable location along the temperature pole 86.

In certain embodiments, at least a portion of the temperature pole 86may be made from a non-ferromagnetic material, such that the temperaturepole 86 has a low permeability for the magnetic flux portion 50. Forexample, the temperature pole 86 may be made of ceramic, composite,plastic, or any other suitable non-ferromagnetic material. In otherembodiments, the distal end 90 of the temperature pole 86 may have ashield 94, as illustrated in FIG. 5. The shield 94 may be coupled to thedistal end 90 of the temperature pole 86 via one or more fasteners, anadhesive or bonding material, a snap-fit joint, a dovetail joint, a hookin slot joint, or any combination thereof. In certain embodiments, theshield 94 is coated onto the distal end 90 of the temperature pole 86.In other embodiments, the integrated circuit coupled to the temperaturesensor 12 may be part of the shield 94. The shield 94 may be anelectromagnetic shield including materials such as, but not limited to,copper, aluminum, phosphor bronze, glass, silicone, composites,polymers, or any other suitable material that may block the transmissionof the magnetic flux portion 50 through the temperature pole 86.

In operation, the sensor head 60 drives an AC current through thedriving coil 32 to induce the magnetic flux portion 50, as discussedabove with reference to FIG. 1. The magnetic flux portion 50 flows fromthe driving pole 28, through the shaft 14, to the four sensing poles 30,where the respective sensing coils 36 detect the magnetic flux portion50. The temperature sensor 12 may monitor the temperature of the shaft14 during rotation by detecting the radiative heat (e.g., the IR heat58) emitted from the shaft 14. Because the temperature pole 86 is in thetorque measurement neutral region 56 and/or has a low magneticpermeability, the magnetic flux portion 50 flowing through the poles 28,30 may not be disturbed by the temperature pole 86. In addition, becausethe temperature sensor 12 is positioned near the shaft 14, at a locationwhere the torque is also being measured, an accurate shaft temperaturemay be obtained. For example, the measured temperature of the shaft 14may be more accurate compared to measuring the shaft temperature in anarea away from the torque measurement location due, in part, to atemperature gradient resulting from dissipation of the IR heat 58.Therefore, because the temperature of the shaft 14 may be measured inreal-time (e.g., during rotation of the shaft 14) and at the location ofthe torque measurement, accurate temperature measurements may begenerated and the accuracy of the compensated torque measurement may beincreased.

Both the sensing coils 36 and the temperature sensor 12 transmitelectrical signals to the controller 42 indicative of the torque andshaft temperature, respectively.

The processor 46 may condition and combine the torque and temperaturesignals to compensate the torque measurement based at least in part oneffects of temperature variations on the magnetic permeability of theshaft 14. As such, the torque measurements generated by the torquesensing system 10 may be more accurate compared to torque sensingsystems that do not have an integrated temperature sensor 12.Integrating the temperature sensor 12 with the torque sensing system 10may enable temperature monitoring during shaft rotation, and mayfacilitate signal integration (e.g., combining the temperature andtorque signals). For example, without the disclosed embodiments,integrating signals from two separate sensors (e.g., throughinterconnecting cables) may increase signal to noise ratios of thesystems due, in part, to noise picked up by the interconnecting cablingduring transmission of the signal. Moreover, integrating torque andtemperature signals generated in a single sensing system (e.g., thetorque sensing system 10) may also facilitate signal processing andincrease accuracy of sensor measurements. Additionally, having a torquesensing system 10 that measures both torque and temperature may reducethe amount of sensing equipment (e.g., stand alone temperature sensorsand torque sensing system) for monitoring operation of the equipment 16,and the overall costs associated with manufacturing two separate sensors(e.g., a temperature sensor and a torque sensor) compared to one sensormay be decreased.

In certain embodiments, the temperature sensor 12 includes a temperaturecoil (e.g., an inductor coil or any other suitable coil), rather than anon-contact IR temperature sensor. FIG. 6 is a perspective view of asensor head 96 having a temperature coil 98. Similar to the sensor head60, the sensor head 96 includes the members 74, 76, 78, 79, and 80extending planarly outward from the yoke portion 70, and the poles 30,86 at terminating ends of each respective member 74, 76, 78, 79, and 80.In the illustrated embodiment, the temperature coil 98 is wrapped aroundthe temperature pole 80. In other embodiments, the temperature coil 98may be wrapped around the driving pole 28. For example, the temperaturecoil 98 may be disposed above or below the driving coil 32.

The temperature coil 98 may transmit an electrical signal to thecontroller 42 indicative of the temperature of the shaft 14. Anelectrical conductivity of the temperature coil 98 may be affected bythe temperature of the shaft 14. For example, the temperature of theradiative heat (e.g., the IR heat 58) emitted from the shaft 14 mayincrease or decrease the conductivity of the temperature coil 98. Thischange in conductivity may be used to determine the temperature of theshaft 14. The processor 46 may use algorithms and/or look-up tablesstored in the memory 48 to determine a temperature of the shaft 14 basedon the change in conductivity of the temperature coil 98.

In certain embodiments, the magnetic flux portion 50 flows through thetemperature pole 86. In this particular embodiment, the temperature pole86 is permeable to the magnetic flux portion 50. That is, thetemperature pole 86 is within a torque measurement neutral region, suchas the torque measurement neutral region 56. The shaft torque may causean anisotropic response in the system 10. In general, temperatureeffects are isotropic and are sensed equally by the coils 32, 36, and98. Therefore, in one embodiment, the system 10 may be oriented in sucha way that the magnetic flux portion 50 flowing through the temperaturepole 86 is insensitive (e.g., unaffected) to the anisotropic changesresulting from the torque. In other embodiments, the poles 28, 30, 86and the coils 32, 36, 98 may each have a different vector orientation.The anisotropic and isotropic components resulting from the shaft torquemay be resolved by the processor 46 (e.g., with analog circuitry ordigital signal processing). In certain embodiments, the sensor head 96does not include the temperature pole 86. As such, the shaft temperatureis determined based on the temperature effects sensed by the coils 32,36 on the poles 28, 30, respectively.

In addition to determining the shaft temperature with the temperaturesensor 12, the temperature of the shaft 14 can be detected inductivelywithout a need to have separate temperature sensing devices. This methodrelies on the changes in the bulk resistivity and/or permeability ofsteel under varying temperature. The changes in the electromagneticproperties of the sensor head 98 affects the penetration depth of themagnetic flux portion 50 that enters the shaft 14. These changes areobserved by the sensing coils 36 and by the drive coil 32. This is due,in part, to the magnetic flux portion 50 going through the shaft 14, thedrive coil 32, and at least one of the plurality of the sense coils 36.The signal changes in the coils 32, 36 are analyzed in parallel with thesignal changes due to torque. The temperature can be resolved, becauseof a relationship between the temperature of the shaft and the bulkeffect common in all the coils 32, 36, resulting from the anisotropy inthe measured signals (e.g., by the coils 32, 36) caused by the shafttorque.

In accordance with the present disclosure, one or more non-contacttemperature sensors 12 may be integrated into the torque sensing device10, such that temperature of the shaft 14 may be measured duringrotation. The temperature sensor 12 is positioned in a magnetic neutralregion (e.g., the torque measurement neutral region 56) of the torquesensing system 10, such that the temperature sensor 12 does notinterfere with torque sensing regions of the torque sensing system 10.In this way, the temperature sensor 12 may be positioned at a torquemeasurement location without disturbing the magnetic flux portion 50.Therefore, accurate temperature measurements may be obtained, enablingaccurate compensation of the torque measurements. In addition,integrating the temperature sensor 12 into the sensor head (e.g., thesensor heads 20, 60, and 96) may facilitate integration of torque andtemperature signals generated by the sensing coils 36 and temperaturesensor 12, respectively, and reduce signal to noise ratios that mayotherwise be introduced during integration of signals from separatetorque and temperature sensors.

Technical effects of the subject matter disclosed herein include, butare not limited to, integrating a non-contact temperature sensor with atorque sensor, such that a temperature of a rotating shaft may beaccurately measured. Advantageously, the resulting torque sensing systemmay compensate torque measurements based at least in part on shafttemperature variations, thereby increasing the accuracy of the torquemeasurements.

This written description uses examples to disclose the invention,including the best mode, and also to enable any person skilled in theart to practice the invention, including making and using any devices orsystems and performing any incorporated methods. The patentable scope ofthe invention is defined by the claims, and may include other examplesthat occur to those skilled in the art. Such other examples are intendedto be within the scope of the claims if they have structural elementsthat do not differ from the literal language of the claims, or if theyinclude equivalent structural elements with insubstantial differencesfrom the literal language of the claims.

1-20. (canceled)
 21. A system, comprising: a magnetostrictive torquesensor comprising a sensor head having a sensing coil configured totransmit a magnetic flux signal and a temperature sensor configured totransmit a temperature signal; and a controller, comprising: one or moretangible, non-transitory, machine-readable media collectively storingone or more sets of instructions; and one or more processing devicesconfigured to execute the one or more sets of instructions, wherein theone or more sets of instructions are configured to: combine the magneticflux singal and the temperature signal to generate a compensated torquesignal, wherein the one or more processing devices is configured todetermine the torque on the rotary structure based on the compensatedtorque signal.
 22. The system of claim 21, wherein the sensor headfurther comprises a driving pole comprising a driving coil configured toreceive a driving current and to emit a magnetic flux portion throughthe rotary structure and a sensing pole comprising the sensing coil,wherein the sensing coil is configured to receive the magnetic fluxportion and to transmit the magnetic flux signal based at least in parton the received magnetic flux portion to the controller, and wherein thereceived magnetic flux portion is based at least in part on a force onthe rotary structure.
 23. The system of claim 21, wherein the controllercomprises a wireless receiver configured to receive the magnetic fluxsignal and the temperature signal, and to transmit the magnetic fluxsignal and the temperature signal to the one or more processing devices.24. The system of claim 21, wherein the one or more sets of instructionsare configured to condition the magnetic flux signal before transmittingthe magnetic flux signal to the one or more processing devices.
 25. Thesystem of claim 21, wherein the controller is integrated into the sensorhead of the magnetostrictive sensor.
 26. The system of claim 21, whereinthe temperature sensor is not in contact with the rotary structure 27.The system of claim 21, wherein the temperature sensor is coupled to atemperature sensing pole of the magnetostrictive torque sensor.
 28. Thesystem of claim 21, wherein the temperature sensor is disposed within amagnetic neutral region of the magnetostrictive torque sensor, and thetemperature sensor comprises an infrared sensor or an induction coil.29. The system of claim 21, wherein the magnetic flux signal is based atleast in part on the torque on a section of the rotary structureopposite the magnetostrictive torque sensor, and the temperature signalis based at least in part on the temperature of the section of therotary structure.
 30. A tangible, non-transitory, machine-readablemedia, comprising: one or more sets of instructions, that when executed,are configured to: combine a torque signal and a temperature signalmeasured by a magnetostrictive torque sensor comprising a sensor headhaving a sensing coil configured to generate the torque signal and atemperature sensor configured to generate the temperature signal,wherein the magnetostrictive torque sensor is configured to measuretorque of a rotary structure; and generate a compensated torque signalbased on the combined torque signal and the temperature signal; anddetermine the torque on the rotary structure based on the compensatedtorque signal.
 31. The tangible, non-transitory, machine-readable mediaof claim 30, wherein the one or more sets of instructions comprises:generating a magnetic flux portion with a driving coil coupled to adriving pole of the magnetostrictive torque sensor; and directing themagnetic flux portion through the rotary structure and a sensing polecomprising the sensing coil.
 32. The tangible, non-transitory,machine-readable media of claim 30, wherein the one or more sets ofinstructions comprises measuring a temperature of the rotary structurewith the temperature sensor.
 33. The tangible, non-transitory,machine-readable media of claim 30, wherein the one or more sets ofinstructions comprises conditioning the torque signal before combiningthe torque signal with the temperature signal, and wherein the torquesignal comprises a magnetic flux portion through the rotary structure.34. The tangible, non-transitory, machine-readable media of claim 30,wherein the one or more sets of instructions comprises conditioning thetemperature signal before combining the temperature signal with thetorque signal.
 35. A kit, comprising: a magnetostrictive sensor having asensor head, wherein the sensor head comprises: a sensor head core: asensing coil coupled to a sensing pole extending from the sensor headcore, wherein the sensing coil is configured to receive a magnetic fluxportion from a rotary structure and to transmit a first signal based atleast in part on the received magnetic flux portion, wherein thereceived magnetic flux portion is based at least in part on a torque ona section of the rotary structure; and a temperature sensor coupled tothe magnetostrictive sensor head, wherein the temperature sensortransmits a second signal based on heat emitted from the section of therotary structure; and a controller configured to receive the firstsignal from the sensing coil and the second signal from the temperaturesensor, wherein the controller comprises: one or more tangible,non-transitory, machine-readable media collectively storing one or moresets of instructions; and one or more processing devices configured toexecute the one or more sets of instructions to control operation of themagnetostrictive sensor, wherein the one or more sets of instructions isconfigured to combine the first signal and the second signal to generatea compensated torque signal, and wherein the one or more processingdevices is configured to determine the torque on the rotary structurebased on the compensated torque signal.
 36. The kit of claim 35, whereinthe magnetostrictive sensor comprises a driving coil coupled to adriving pole extending from the sensor head core, wherein the drivingcoil is configured to receive a driving current and to emit the magneticflux portion through the rotary structure.
 37. The kit of claim 35,wherein the controller is integrated into the sensor head core.
 38. Thekit of claim 35, wherein the temperature sensor comprises an infraredsensor or an inductive coil.
 39. The kit of claim 35, wherein themagnetostrictive sensor comprises a temperature pole extending from thesensor head core, wherein the temperature sensor is disposed adjacent toa terminating end of the temperature pole.
 40. The kit of claim 35,wherein the section of the rotary structure is opposite themagnetostrictive sensor head.